Q&A - PSLE Math

[Shimmer]

Please help need urgent


Luna had 50% more marbles than Rome. When Luna and Rome each gave 14% of their marbles to Sira, the no. of marbles Sira had increase to 70%. In the end, Luna had 88 more than Sira. How marbles Rome had at first ?

[PiggyLalala]

jarenchuatw:

Help, pls...


At a prefect investiture, prefects could bring either one or both their parents along. If the ratio of the number of prefects to the number of parents who attended was 7:9 and 1/7 of the prefects brought only 1 parent, what fraction of the prefects did not bring any parents along?

My answer is 2/7

[PiggyLalala]

Winx5015:

Following are some math prelim 2011 (paper 2) questions, can anyone help?


1). 1 notebook and 1 wallet cost $8.30.
2 wallets and 2 pens cost $18.
3 pens and 3 notebooks cost $16.50.
Find the total cost of 3 notebooks, 4 wallets and pens.

2). Four sisters Anne, Betty, Chels and Dorothy shared the cost of a travel package to Switzerland. The contribution made by Anne is 1/2 that of the total contribution made by the other three sisters. Contribution made by Betty is 1/4 of the total contribution made by the other three sisters and the contribution made by Chels is 2/3 of the total contribution made by the other three sisters. If the total price of the package is $9900, find the contribution made by Dorothy.

3). Tank A is 1/2 filled with water. Tank B, which has twice the capacity of Tank A, is 1/3 filled with water. When water in Tank B is poured into Tank A until Tank A is completely filled with water to the brim, Tank B contained some water.
a). What fraction of Tank B's capacity is the fraction of the remaining water in Tank B?
b). Given that the length and breadth of Tank B are 34cm by 15cm respectively, what is the height of Tank B if the remaining volume of water in Tank B is 3.4 litres?

4). At a jewellery shop, 40% of the items are brooches. The remainder are rings and bangles. For every bangle, there are 4 rings.
a). Find the ratiio of brooches to bangles to rings. (Give your answer in simplest form)
b). There are 48 more rings than brooches. After some brooches were sold and none of the rings and bangles were sold, 20% of the remaining items at the jewellery shop are brooches. How many brooches were left?

Thanks for helping

Is the answer for Q2: $660

[Neat]

Hi!


I need help!

Please assist on the following question:

Four girls each has some money. Kyna has 1/3 of the total amount of money that Lynn, Gigi and Tin Wing have. Lynn has 1/4 of the total amount of money that Kyna, Gigi and Tin Wing have. Gigi has 1/5 of the total amount of money Kyna, Lynn and Tin Wing have. If Tin Wing has $368, how much money do the four girls have altogether?

Thanks

[2DMommy]

Please help me with the following questions :


1) 5 friends were playing Wii games on a Fri afternoon from 3 pm to 6 pm. As there were only 4 consoles, they took turns to play. At any time, 3 of them played while the other 2 friends watched. If each of them had the same amount of playing time, how many minutes did each child play that afternoon?

2) An MRT train set off from 1st station with some passengers on board. The ratio of the number of men to that of women was 5:3. At the 2nd station 3/7 of men and some women alighted. Then the ratio of the number of men to that do women became 10:7. At the 3rd station, 70 men and 196 women got on the train and the number of men was the same as the number of women.
a) how many passengers were there on board the train when it set off from the 1st station?
b) how many women alighted at the 2nd station?

Thank you.

[underthesea]

Please help with this question,


Lily is meeting a friend at a certain time. If she drives at 80km/h, she will be 1/3hour late. If she drives at 60km/h, she will be 3/4 hour late. How long will the journey take if she drives at 90km/h?

TIA.

[tianzhu]

underthesea:

Please help with this question,


Lily is meeting a friend at a certain time. If she drives at 80km/h, she will be 1/3hour late. If she drives at 60km/h, she will be 3/4 hour late. How long will the journey take if she drives at 90km/h?

TIA.

Hi

Good Morning.

A similar question has been discussed before.

There are a few approaches.

Hope this helps.

Best wishes.

http://farm5.staticflickr.com/4140/4803808352_3c514a8732_z.jpg\">

http://farm5.staticflickr.com/4114/4803808434_56d6854757_z.jpg\">

http://farm5.staticflickr.com/4078/4803267503_d2c34633b8_z.jpg\">

[tianzhu]

Neat:

Hi!


I need help!

Please assist on the following question:

Four girls each has some money. Kyna has 1/3 of the total amount of money that Lynn, Gigi and Tin Wing have. Lynn has 1/4 of the total amount of money that Kyna, Gigi and Tin Wing have. Gigi has 1/5 of the total amount of money Kyna, Lynn and Tin Wing have. If Tin Wing has $368, how much money do the four girls have altogether?

Thanks

Hi

Good Morning.

Make the total number of units the same. A common multiple is 60.

K:(L+G+TW) ------ 1:3 (4) ------ 15:45 (60)

L:(K+G+TW) ------ 1:4 (5) ------- 12:48 (60)

G:(K+L+TW) ------ 1:5(6) ------- 10:50 (60)

TW ------ 60 – (15+12+10) ------ 23

23 units ------- 368

1 unit ------- 16

Total amount of money ------ 60*16 -------- 960

Best wishes

[tianzhu]

2DMommy:

Please help me with the following questions :

1) 5 friends were playing Wii games on a Fri afternoon from 3 pm to 6 pm. As there were only 4 consoles, they took turns to play. At any time, 3 of them played while the other 2 friends watched. If each of them had the same amount of playing time, how many minutes did each child play that afternoon?

Hi

Good Morning.

From 3 pm to 6 pm ----- 3h ------ 180 minutes

At any time, 3 of them played while the other 2 friends watched.

180*3 ------- 540

540/5 ------ 108

Best wishes

[Studious Alien]

tianzhu:

Winx5015:

http://i45.tinypic.com/kd8r36.jpg\">

Hi

It's difficult to read your image as it's small.

It looks like this question which was discussed earlier.

Best wishes

http://farm7.staticflickr.com/6063/6139917034_a6c214361a_z.jpg\">

Hi tianzhu,
After seeing your diagram, I do not understand the green arrows part. Please assist. :scratchhead: